Almost half of Americans believe Facebook is a passing fad. 46 percent believe it "will fade away as new things come along," 43 percent believe it "will be successful over the long term," and 11 percent don't know what to think.

The data comes from a CNBC poll of 1,004 U.S. adults. They were polled between May 3 and May 7 via landline and cell phone interviews, and the results have a margin of sampling error of plus or minus 3.9 percentage points.

Here are the three points shared in relation to the above graph:

Investors are more optimistic than others about the company's long-term prospects. 48 percent think it will be successful in the long run compared with 42 percent of non-investors.

There's a sharp divide on this question among users and non-users of the site. Fifty-one percent of users see it as a long-term success versus just 35 percent among non-users.

Although they are generally more positive about the company, younger adults are no more apt than their older counterparts to expect Facebook's long-term success; 51 percent think it will fade.

On the flipside, a majority of those surveyed (51 percent) have a favorable impression of the company, while 23 percent have an unfavorable opinion.

Here are 10 other notable findings:

About half (51 percent) say Facebook stock would be a good investment to make while 31 percent say it would not be so good and 17 percent just aren't sure.

Among those who own stocks, bonds or mutual funds, 54 percent say Facebook would be a good investment, 34 percent say it would not. Active investors (38%) are more likely than other investors (30%) to say it wouldn't be a good investment.

Half of Americans (50 percent) say a Facebook valuation of nearly one hundred billion dollars - larger than Ford and Kraft but smaller than Google and Coca-Cola - would be too high. Among active investors, 62 percent say they think Facebook will be overvalued, 27 percent think it will be fairly priced and 5 percent believe it will be undervalued.

A majority (59%) of Facebook users do not trust the site with their personal information and have little or no faith in the company to protect their privacy. A slight minority (13%) trust the company completely or a lot.

About 8 in 10 Facebook users surveyed say they hardly ever (26%) or never (57%) click on online advertising or sponsored content when using the site.

Most (54%) say they would not feel safe purchasing goods and services on Facebook. Among the site's most frequent users, half say they would not feel safe making purchases through the site.

Just 18 percent of Americans have deep confidence in Zuckerberg's ability to run a large publicly traded company like Facebook, another 40 percent say they are "somewhat confident."

About a third of the public (36%) has a favorable impression of the Facebook founder, while 14 percent hold an unfavorable opinion and 20 percent say they've never heard of him or don't know how they feel. Among active investors, 42 percent have a mostly positive impression of Zuckerberg while 14 percent view him unfavorably.

The Social Network filmgoers have a more favorable impression of Zuckerberg than others (51% favorable compared to 31% among those who have not seen it).

More than 4 in 10 said Zuckerberg's age would have little impact on his leadership abilities. His age is actually seen more as an asset (21 percent help) than a liability (11 percent hurt).